US president Joe Biden took a tumble as he boarded Air Force One.
The president stumbled up the stairs at Joint Base Andrews in Maryland as he prepared to travel to Atlanta in Georgia, where he was to speak to the Asian-American community about a shooting there this week.
Mr Biden stumbled slightly about halfway up the 25 or so stairs, recovered, then stumbled again and briefly went down on one knee, according to video footage.
The president appeared to rub his left knee before getting back up, then completed the stairs at a slower pace. He stopped at the top of the stairs, turned around and offered a crisp salute to the military officers who had greeted him earlier on the tarmac.
Later, White House principal deputy press secretary Karine Jean-Pierre said President Biden was “doing 100 per cent fine”.
She suggested high winds at Joint Base Andrews near Washington may have been a factor.
"It's very windy outside," said Ms Jean-Pierre when asked about his stumbling. "He is doing 100 per cent fine."
She did not say whether Mr Biden had been checked by a travelling physician after the episode.
In late November, Mr Biden suffered a hairline fracture in his right foot while playing with one of his dogs.
At 78, Mr Biden was the oldest person ever to assume the presidency when he entered the White House on January 20th.
